Method for producing gas-containing insulating glass assemblies

Abstract

The invention relates to a method of producing a plurality of multi-pane insulating glass assemblies (70) in which the assemblies (70) are formed into a self-supporting unit for further fabrication. Each assembly (70) is provided with at least one exteriorly accessible opening, and the assemblies (70), supporting one another in surface-to-surface contact, are moved along a conveyor as a unit into a vacuum chamber (10). Vacuum is drawn on the unit to evacuate each interpane space, following which a gas having coefficient of thermal conductivity lower than that of air is introduced into the chamber (10) to fill the interpane spaces of the glass assemblies (70). The assemblies (70) as a unit are then conveyed out of the vacuum chamber (10) and the exteriorly accessible openings are sealed. During the evacuation and refilling steps, the glass assemblies are maintained in a generally vertical orientation, and each glass assembly (70) is supported by a neighboring assembly against undue bowing of the glass panes due to pressure differentials between the interior of the vacuum chamber and the interpane spaces.

What is claimed is: 
     
       1. Method for fabricating multi-pane insulating glass assemblies each having a sealed interpane space and each containing a gas having a coefficient of thermal conductivity lower than that of air, comprising: a. providing a plurality of glass assemblies, each comprising at least a pair of aligned, parallel, spaced glass panes having confronting surfaces defining therebetween an air-containing interpane space and having a spacer carried peripherally between the panes, each assembly having at least one exteriorly accessible peripheral opening through which gas may flow into and out of the interpane space, the panes of the plurality of glass assemblies extending in parallel, generally vertical planes and at least one pane of each assembly supporting a pane of a neighboring assembly;   b. moving the plurality of glass assemblies as a unit into a chamber;   c. evacuating the chamber to draw substantially all of the air from the interpane spaces;   d. flowing into the evacuated chamber a gas having a coefficient of thermal conductivity lower than that of air, the gas refilling and occupying the interpane space; the flow rates of air and gas from and into the chamber being so controlled as to prevent the pressure differential across the at least one opening of each assembly from exceeding about 4 psi;   e. removing the glass assemblies as a unit from the chamber; and   f. closing the at least one opening in each assembly to seal gas within the interpane space thereof.   
     
     
       2. The method of claim 1 wherein the at least one exteriorly accessible opening extends through the thickness of a spacer located at the top of each assembly as the assemblies are removed from the chamber as a unit. 
     
     
       3. The method of claim 2 wherein the glass assemblies are generally rectangular and wherein the at least one exteriorly accessible opening is positioned at an upper corner of each of the assemblies as the latter are removed from the chamber. 
     
     
       4. The method of claim 3 including the step of inserting a plug into each opening to seal the same against gas escape. 
     
     
       5. The method of claim 4 wherein the plug is an expanding head rivet. 
     
     
       6. The method of claim 1 including the step of flowing said gas into the chamber to a final chamber pressure slightly greater than ambient atmospheric pressure. 
     
     
       7. The method of claim 3 wherein the glass assemblies each include a spacer comprising a hollow channel having ends abutting at one assembly corner and having a solid corner key received within the hollow abutting ends of the spacer, said exteriorly accessible opening being formed through the corner key. 
     
     
       8. The method of claim 1 wherein the planes defined by the plurality of glass assemblies are maintained at an angle of about 15° to the vertical while in the chamber. 
     
     
       9. The method of claim 1 wherein adjacent glass assemblies have panes supporting one another throughout substantially their entire areas. 
     
     
       10. The method of claim 9 including the step of poviding protective sheets between confronting surfaces of neighboring glass assemblies. 
     
     
       11. Method for fabricating multi-pane insulating glass units each having sealed interpane spaces comprising the steps of: a. providing a plurality of glass assemblies each comprising a pair of aligned, spaced glass panes having therebetween a peripheral spacer, the panes having confronting surfaces defining with the spacer an air containing interpane space, each assembly having an exteriorly accessible peripheral opening adjacent a corner thereof through which gas may flow into and out of the interpane space;   b. positioning said glass assemblies in aligned, adjacent, generally vertical planes with at least one pane of each assembly supporting a pane of an adjacent assembly in surface-to-surface contact through an intermediate protective sheet;   c. moving the plurality of mutually supporting glass assemblies as a unit into a chamber, and evacuating the chamber to draw substantially all of the air from the interpane spaces;   d. flowing into the evacuated chamber a gas having a coefficient of thermal conductivity lower than that of air, the gas refilling and occupying the interpane space;   e. the rates of flow of air from the chamber and gas to the chamber being regulated so as to prevent the pressure differential across the at least one opening of each assembly from exceeding about 4 psi;   f. removing the unit of glass assemblies from the chamber; and closing the opening in each assembly to seal therewithin the gas.   
     
     
       12. Method for fabricating multi-pane insulating glass assemblies each having a sealed interpane space and each containing a gas having a coefficient of thermal conductivity lower than that of air, comprising: a. providing a plurality of glass assemblies, each comprising at least a pair of aligned, parallel, spaced glass panes having confronting surfaces defining therebetween an air-containing interpane space and having a spacer carried peripherally between the panes, each assembly having at least one exteriorly accessible peripheral opening extending through the thickness of a spacer located at the top of each assembly and through which gas may flow into and out of the interpane space, the panes of the plurality of glass assemblies extending in parallel, generally vertical planes and at least one pane of each assembly supporting a pane of a neighboring assembly;   b. moving the plurality of glass assemblies as a unit into a chamber;   c. evacuating the chamber to draw substantially all of the air from the interpane spaces;   d. flowing into the evacuated chamber a gas having a coefficient of thermal conductivity lower than that of air, the gas refilling and occupying the interpane space;   e. removing the glass assemblies as a unit from the chamber; and   f. while maintaining the position of the assemblies as the same are removed from the chamber as a unit so that the at least one exteriorly accessible opening extends through the thickness of a spacer located at the top of each assembly, closing the at least one opening in each assembly to seal gas within the interpane space thereof.   
     
     
       13. The method of claim 12 wherein the flow rates of air and gas from and into the chamber are controlled so as to prevent the pressure differential across the at least one opening of each assembly from exceeding about 4 psi. 
     
     
       14. Method for fabricating multipane insulating glass assemblies comprising providing a plurality of glass assemblies each comprising a pair of aligned, parallel spaced glass panes having confronting surfaces defining between then an air containing interpane space and having a spacer carried peripherally between the panes, each assembly having at least one exteriorly accessible peripheral opening, the panes of the plurality of glass assemblies extending in parallel, generally vertical planes and at least one pane of each assembly supporting a pane of a neighboring assembly; moving the plurality of glass assemblies as a unit into a chamber; evacuating the chamber to draw substantially all of the air from the interpane spaces through the at least one exteriorly accessible peripheral opening of each assembly; flowing into the evacuated chamber a gas having a coefficient of thermal conductivity lower than that of air, the gas refilling the interpane space through the exteriorly accessible peripheral opeings; removing the glass assemblies as a unit from the chamber; and closing the at least one opening in each assembly to seal gas within its interpane space.   
     
     
       15. The method of claim 14 including the step of leaning the glass assemblies supportively against one another, the parallel planes defined by the glass panes being angled from the vertical.